Mod S
| transponder
| mod S | |
| commun. transp. avia. | Mode Select; Mode S |
| transponder | |
| commun. IT | remodulating baseband radio |
| el. | transponder |
| |||
| Mode Select; Mode S | |||
|
Mod S : 8 phrases in 2 subjects |
| Communications | 6 |
| Transport | 2 |